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In this study, we used computational design and protein engineering to modify stabilizing protein 1 to mimic glutathione peroxidase (GPx), and constructed a reversible protein-assembled nanoscale artificial selenidase based on Ni2+-response. Its unique glutathione substrate recognition site and spatial orientation of the Se active center endow it with high GPx activity. The experimental results showed that the spatial barrier formed by Ni2+-induced assembly can inhibit enzyme activity, and EDTA can dissociate and restore activity. And the reversible protein assembly system is robust after multiple cycles, demonstrating the potential of this "intelligent" artificial selenoenzymatic nanomaterials for controllable catalytic applications in biomedicine. [ABSTRACT FROM AUTHOR]

The review examines the main stages of cytokinin biosynthesis and metabolism with an emphasis on the important role of cytokinin oxidase/dehydrogenase (CKO/CKX) in cytokinin degradation. In this context, arguments are made for the crucial importance of this enzyme in maintaining a balanced level of cytokinins in plants. The role of CKX genes encoding cytokinin oxidase/dehydrogenase in determining plant resistance to abiotic stress factors and their yield was analyzed. The molecular genetic ways of regulating the activity of CKX genes are characterized. The results of research on the regulation of CKO/CKX activity in increasing the resistance to abiotic stress and crop yield are summarized and the biotechnological ways of realizing such opportunities are described. Prospects for finding substances that inhibit CKO/CKX activity to create preparations for agriculture are outlined separately. Prospective chemical inhibitors of CKO/CKX and their effects on cultivated plants are considered. [ABSTRACT FROM AUTHOR]

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DNA polymerase λ (Polλ) belongs to the same structural X-family as DNA polymerase β, the main polymerase of base excision repair. The role of Polλ in this process remains not fully understood. A significant difference between the two DNA polymerases is the presence of an extended non-catalytic N-terminal region in the Polλ structure. The influence of this region on the interaction of Polλ with DNA and multifunctional proteins, poly(ADP-ribose)polymerase 1 (PARP1) and replication protein A (RPA), was studied in detail for the first time. The data obtained suggest that non-catalytic Polλ domains play a suppressor role both in relation to the polymerase activity of the enzyme and in interaction with DNA and PARP1. [ABSTRACT FROM AUTHOR]

Glucose oxidase (GOD) is an oxidoreductase that catalyzes the aerobic oxidation of glucose into hydrogen peroxide (H2O2) and gluconic acid, which has been widely used in industrial raw materials production, biosensors and cancer treatment. However, natural GOD bears intrinsic disadvantages, such as poor stability and a complex purification process, which undoubtedly restricts its biomedical applications. Fortunately, several artificial nanomaterials have been recently discovered with a GOD-like activity and their catalytic efficiency toward glucose oxidation can be finely optimized for diverse biomedical applications in biosensing and disease treatments. In view of the notable progress of GOD-mimicking nanozymes, this review systematically summarizes the representative GOD-mimicking nanomaterials for the first time and depicts their proposed catalytic mechanisms. We then introduce the efficient modulation strategy to improve the catalytic activity of existing GOD-mimicking nanomaterials. Finally, the potential biomedical applications in glucose detection, DNA bioanalysis and cancer treatment are highlighted. We believe that the development of nanomaterials with a GOD-like activity will expand the application range of GOD-based systems and lead to new opportunities of GOD-mimicking nanomaterials for various biomedical applications. [ABSTRACT FROM AUTHOR]

Nanozymes have been viewed a kind of emerging nanomaterials with enzyme-mimicking catalytic activity, which have the advantage of low cost and good robustness. However, the complex nano-effect and surface interface effect of nanozymes hinder the in-depth understanding of their enzyme-like catalytic activities and the development of highly active nanozymes to some extent. To date, metal-organic frameworks (MOFs)-based nanozymes have been widely exploited due to the unique structural characteristics and customizability, which can mimic the active center and hydrophobic domain of natural enzymes, providing great opportunities in rationally developing MOFs with enhanced catalytic activity. Herein, we systematically summarize the activity regulatory strategies of MOFs-based nanozymes and their applications in biosensing. Firstly, the engineering design strategies containing modulation of metal node, ligand, defect, morphology, and topology are introduced. Then, the distinctive applications of MOFs-based nanozymes in biosensing are also discussed. At the end, the recent challenges and progressive directions are tentatively proposed. [Display omitted] • Engineering MOFs-based nanozymes for enhanced biosensing. • The de novo design of MOFs-based nanozymes. • Activity regulatory strategies of MOFs-based nanozymes. • The current challenges and future prospects of MOFs-based nanozymes. [ABSTRACT FROM AUTHOR]

Glucose oxidase (GOD) is an oxidoreductase that catalyzes the aerobic oxidation of glucose into hydrogen peroxide (H2O2) and gluconic acid, which has been widely used in industrial raw materials production, biosensors and cancer treatment. However, natural GOD bears intrinsic disadvantages, such as poor stability and a complex purification process, which undoubtedly restricts its biomedical applications. Fortunately, several artificial nanomaterials have been recently discovered with a GOD-like activity and their catalytic efficiency toward glucose oxidation can be finely optimized for diverse biomedical applications in biosensing and disease treatments. In view of the notable progress of GOD-mimicking nanozymes, this review systematically summarizes the representative GOD-mimicking nanomaterials for the first time and depicts their proposed catalytic mechanisms. We then introduce the efficient modulation strategy to improve the catalytic activity of existing GOD-mimicking nanomaterials. Finally, the potential biomedical applications in glucose detection, DNA bioanalysis and cancer treatment are highlighted. We believe that the development of nanomaterials with a GOD-like activity will expand the application range of GOD-based systems and lead to new opportunities of GOD-mimicking nanomaterials for various biomedical applications.

Nanozymes are nanomaterials that exhibited high enzymatic activities and considered as a better alternative to natural enzymes. These nanoparticles are characterized by unique properties such as high catalytic activity with high stability, easy and low cost preparation. The multi-functional feature of nanozymes enables them to be applied in a wide range of applications such as biosensing, immunoassays, diseases diagnosis and therapeutics as well environmental management. In this context, this review provides a comprehensive overview about these nanoparticles, especially their types, preparation, characterization and enzymatic activities. In addition, some of their potential applications in the biocontrol of multi-drug resistant bacteria, medical field as well as environmental pollutants detection and removal have been highlighted. Nanozymes with both unique physicochemical properties of nanoparticles and enzyme-mimicking catalytic properties will attract a broad interest of scientists and offer promising strategies for diagnosis and treatment of many diseases and handling current environmental problems. [ABSTRACT FROM AUTHOR]

• Bionic modulation of catalytic activity of MOF nanozymes via a facile approach. • Increasing the amount of histidine modification to enhance the catalytic activity. • The established structure-activity of MOF nanozyme can direct practical sensing. • Pesticide detection by the sensor arrays is highly discriminatory and quantitative. Biosensors provide simple, rapid and sensitive detection of a wide range of analytes. Recently, they have been widely used for the rapid detection of pesticides, which makes up for the shortcomings of traditional detection methods. However, the catalytic activity of some nanozymes is not satisfactory in practical applications, limiting the performance of biosensors. Further development of highly active and stable nanozymes is conducive to improving the sensitivity of the sensors and expanding their application in practical detection. Herein we simulated the amino acid microenvironment of natural enzymes and synthesized His-MIL-101(Fe)-X with different histidine (His) modification amounts (X = 0, 25%, 50%, 75%) by regulating the ratio of histidine and terephthalic acid ligands using a one-step solvothermal method. With increasing histidine doping, the peroxidase-like activity of His-MIL-101(Fe)-X was gradually enhanced, and the sensing performance of the sensor arrays constructed by combining His-MIL-101(Fe)-X with three peroxidase substrates was also gradually improved, with a 25-fold increase in detection limit. The His-MIL-101(Fe)-75% sensor array was not only able to accurately discriminate five pesticides in the range of 2-100 μM, but also to quantitatively identify different concentrations of pesticides. Moreover, the His-MIL-101(Fe)-75% sensor array showed good anti-interference capability and was able to discriminate five pesticides at only 2 μM in soil, lake water, seawater, and apple samples, as well as quantitatively detecting diafenthiuron, which has great potential for practical application. [ABSTRACT FROM AUTHOR]

The iron oxide nanoparticles (IONPs) that combine the nanozyme activity and magnetothermal properties have attracted significant interest for various biomedical applications. However, the effect of magnetic stimulation in fine-tuning the nanozyme activities remains unclear. Here, we have constructed a series of IONPs with different magneto-thermal conversion abilities, and systematically study the effect of magnetic field stimulation on the peroxidase (POD) activity of IONPs. The results show that POD activity is effectively amplified via an in situ alternating magnetic field (AMF) stimulation with no solution temperature rise, and the degree of activity enhancement is closely related to the magnetic heating ability of the IONPs, confirming the origin of activity enhancement arises from the local magnetothermal effect. As the first report to prove magnetothermal regulation on nanozyme activity and to shed lights on the underlying correlation between activity enhancement and the intrinsic specific absorption rate (SAR), this work is expected to provide important support for future design of new magnetoresponsive nanozymes in various practical applications. [ABSTRACT FROM AUTHOR]

The purpose of the research is to determine the main directions for improving the system of evaluating work and positions and adapting the known principles of labor analysis to personnel. The dynamic development of the personnel management system and innovation in production and business activities has led to an increase in the demand for socio-economic systems for the innovative development of personnel systems and their constant updating, increasing demand for highly qualified, creative personnel, and requires constant training of workers in accordance with the requirements to the positions. The currently used analysis of work includes the most diverse aspects of developments in the field of organizational thinking and serves as the basis for obtaining a more objective basis for describing job descriptions, determining training needs and wages. Lifelong learning is becoming an imperative of our time and one of the main conditions for the formation of competitive advantages of labor resources and organizations.A theoretical study confirms the growing role of labor analysis and the transformation of the latter into a leading factor in the modern organization of labor. The practical significance of the research results consists in a comparative analysis of the most popular assessment methods, as well as the possibilities of their use to improve work of personnel.

Mass behavior is the rapid adoption of similar conduct by all group members, with potentially catastrophic outcomes such as mass panic. Yet, these negative consequences are rare in integrated social systems such as social insect colonies, thanks to mechanisms of social regulation. Here, we test the hypothesis that behavioral deactivation between active individuals is a powerful social regulator that reduces energetic spending in groups. Borrowing from scaling theories for human settlements and using behavioral data on harvester ants, we derive ties between the hypermetric scaling of the interaction network and the hypometric scaling of activity levels, both relative to the colony size. We use elements of economics theory and metabolic measurements collected with the behavioral data to link activity and metabolic scalings with group size. Our results support the idea that metabolic scaling across social systems is the product of different balances between their social regulation mechanisms., (© The Author(s) 2024. Published by Oxford University Press on behalf of National Academy of Sciences.)

Patients with chronic fatigue receive advice to improve symptom management and well-being. This advice is based on ideas of self-management and is conveyed during clinical assessment as "activity regulation." Based on ethnographic fieldwork in a hospital clinic in Norway, we show how these patients attempt to demonstrate their competences and everyday concerns, and how the ideology of self-management frames the hope for recovery and crafts a subject with the ability to improve. Patients, however, linger between everyday social predicaments and ideals of healthy living, and are caught up in cultural models of care that deflect everyday concerns and agency. [ABSTRACT FROM AUTHOR]

Homopolymeric amino acid repeats are found in about 24 % of human proteins and are over-represented in transcriptions factors and kinases. Although relatively rare, homopolymeric histidine repeats (polyH) are more significantly found in proteins involved in the regulation of embryonic development. To gain a better understanding of the role of polyH in these proteins, we used a bioinformatic approach to search for shared features in the interactomes of polyH-containing proteins in human. Our analysis revealed that polyH protein interactomes are enriched in cysteine-rich proteins and in proteins containing (a) cysteine repeat(s). Focusing on HOXA1, a HOX transcription factor displaying one long polyH motif, we identified that the polyH motif is required for the HOXA1 interaction with such cysteine-rich proteins. We observed a correlation between the length of the polyH repeat and the strength of the HOXA1 interaction with one Cys-rich protein, MDFI. We also found that metal ion chelators disrupt the HOXA1-MDFI interaction supporting that such metal ions are required for the interaction. Furthermore, we identified three polyH interactors which down-regulate the transcriptional activity of HOXA1. Taken together, our data point towards the involvement of polyH and cysteines in regulatory interactions between proteins, notably transcription factors like HOXA1. • Poly-histidine (polyH) is the most overrepresented amino acid repeat in developmental proteins. • PolyH and cysteine-rich domains can serve as interacting interfaces in protein-protein interaction. • This interaction is coordinated around a metal ion. • The length of the polyH motif influences the strength of this interaction. • PolyH serves as interacting motif for the regulation of the HOXA1 transcriptional activity. [ABSTRACT FROM AUTHOR]

Glutamate dehydrogenase (GDH) is an important enzyme in ammonium metabolism, the activity of which is regulated by multiple factors. In this study, we investigate the effects of ammonium and potassium on the activity of maize GDH. Our results show that both ammonium and potassium play multiple roles in regulating the activity of maize GDH, with the specific roles depending on the concentration of potassium. Together with the structural information of GDH, we propose models for the substrate inhibition of ammonium, and the elimination of substrate inhibition by potassium. These models are supported by the analysis of statistic thermodynamics. We also analyze the binding sites of ammonium and potassium on maize GDH, and the conformational changes of maize GDH. The findings provide insight into the regulation of maize GDH activity by ammonium and potassium and reveal the importance of the dose and ratio of nitrogen and potassium in crop cultivation. [ABSTRACT FROM AUTHOR]

Cancer, as one of the leading causes of death worldwide, drives the advancement of cutting-edge technologies for cancer treatment. Transition-metal-based nanozymes emerge as promising therapeutic nanodrugs that provide a reference for cancer therapy. In this review, we present recent breakthrough nanozymes for cancer treatment. First, we comprehensively outline the preparation strategies involved in creating transition-metal-based nanozymes, including hydrothermal method, solvothermal method, chemical reduction method, biomimetic mineralization method, and sol-gel method. Subsequently, we elucidate the catalytic mechanisms (catalase (CAT)-like activities), peroxidase (POD)-like activities), oxidase (OXD)-like activities) and superoxide dismutase (SOD)-like activities) of transition-metal-based nanozymes along with their activity regulation strategies such as morphology control, size manipulation, modulation, composition adjustment and surface modification under environmental stimulation. Furthermore, we elaborate on the diverse applications of transition-metal-based nanozymes in anticancer therapies encompassing radiotherapy (RT), chemodynamic therapy (CDT), photodynamic therapy (PDT), photothermal therapy (PTT), sonodynamic therapy (SDT), immunotherapy, and synergistic therapy. Finally, the challenges faced by transition-metal-based nanozymes are discussed alongside future research directions. The purpose of this review is to offer scientific guidance that will enhance the clinical applications of nanozymes based on transition metals.

Homopolymeric amino acid repeats are found in about 24 % of human proteins and are over-represented in transcriptions factors and kinases. Although relatively rare, homopolymeric histidine repeats (polyH) are more significantly found in proteins involved in the regulation of embryonic development. To gain a better understanding of the role of polyH in these proteins, we used a bioinformatic approach to search for shared features in the interactomes of polyH-containing proteins in human. Our analysis revealed that polyH protein interactomes are enriched in cysteine-rich proteins and in proteins containing (a) cysteine repeat(s). Focusing on HOXA1, a HOX transcription factor displaying one long polyH motif, we identified that the polyH motif is required for the HOXA1 interaction with such cysteine-rich proteins. We observed a correlation between the length of the polyH repeat and the strength of the HOXA1 interaction with one Cys-rich protein, MDFI. We also found that metal ion chelators disrupt the HOXA1-MDFI interaction supporting that such metal ions are required for the interaction. Furthermore, we identified three polyH interactors which down-regulate the transcriptional activity of HOXA1. Taken together, our data point towards the involvement of polyH and cysteines in regulatory interactions between proteins, notably transcription factors like HOXA1., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2023 Elsevier B.V. All rights reserved.)

While the functions of HOX genes have been and remain extensively studied in distinct model organisms from flies to mice, the molecular biology of HOX proteins remains poorly documented. In particular, the mechanisms involved in regulating the activity of HOX proteins have been poorly investigated. Nonetheless, based on data available from other well-characterized transcription factors, it can be assumed that HOX protein activity must be finely tuned in a cell-type-specific manner and in response to defined environmental cues. Indeed, records in protein–protein interaction databases or entries in post-translational modification registries clearly support that HOX proteins are the targets of multiple layers of regulation at the protein level. In this context, we review here what has been reported and what can be inferred about how the activities of HOX proteins are regulated by their intracellular distribution.

DesK is a Bacillus thermosensor kinase that is inactive at high temperatures but turns activated when the temperature drops below 25 °C. Surprisingly, the catalytic domain (DesKC) lacking the transmembrane region is more active at higher temperature, showing an inverted regulation regarding DesK. How does the transmembrane region control the catalytic domain, repressing activity at high temperatures, but allowing activation at lower temperatures? By designing a set of temperature minimized sensors that share the same catalytic cytoplasmic domain but differ in number and position of hydrogen-bond (H-bond) forming residues along the transmembrane helix, we are able to tune, invert or disconnect activity from the input signal. By favoring differential H-bond networks, the activation peak could be moved towards lower or higher temperatures. This principle may be involved in regulation of other sensors as environmental physicochemical changes or mutations that modify the transmembrane H-bond pattern can tilt the equilibrium favoring alternative conformations. [ABSTRACT FROM AUTHOR]

This chapter describes a methodology for the screening and characterization of functional circRNAs, particularly in the context of neural circuit development. Taking advantage of a primary rat neuron culture model of synaptogenesis, we propose a means of selecting from the plethora of circRNA species based on their expression levels, dendritic localization, conservation, and activity regulation. These candidates are then knocked down with RNAi approaches in a functional screen for their potential role in the formation and maturation of excitatory synapses.Upon identification of top candidates regulating synaptogenesis, we tie together different "Omics" approaches to explore the molecular mechanisms underlying the phenotypes observed upon circRNA knockdown. We utilized our EnrichMir algorithm to identify overrepresented miRNA binding sites in differentially expressed genes from polyA-RNA-seq following circRNA knockdown. Furthermore, our ScanMiR web tool allows for the miRNA binding prediction of reconstructed internal circular RNA sequences. Small-RNA sequencing is used to monitor changes in miRNA levels in the circRNA knockdown to complement results obtained from EnrichMiR. Finally, the experimental validation of promising miRNA-circRNA pairs sets the stage for in-depth biochemical exploration of the circRNA interactome and mechanism of action., (© 2024. The Author(s), under exclusive license to Springer Science+Business Media, LLC, part of Springer Nature.)

Nucleotide excision repair (NER) is one of the major DNA repair pathways aimed at maintaining genome stability. Correction of DNA damage by the NER system is a multistage process that proceeds with the formation of multiple DNA-protein and protein-protein intermediate complexes and requires precise coordination and regulation. NER proteins undergo post-translational modifications, such as ubiquitination, sumoylation, phosphorylation, acetylation, and poly(ADP-ribosyl)ation. These modifications affect the interaction of NER factors with DNA and other proteins and thus regulate either their recruitment into the complexes or dissociation from these complexes at certain stages of DNA repair, as well as modulate the functional activity of NER proteins and control the process of DNA repair in general. Here, we review the data on the post-translational modifications of NER factors and their effects on DNA repair. Protein poly(ADP-ribosyl)ation catalyzed by poly(ADP-ribose) polymerase 1 and its impact on NER are discussed in detail, since such analysis has not been done before. [ABSTRACT FROM AUTHOR]

Fungal lipases are efficient and environment‐friendly biocatalysts for many industrially relevant processes. One of the most widely applied lipases in the manufacturing industry is Candida antarctica lipase B (CALB). Here, we report the biochemical and structural characterization of a novel CALB‐like lipase from an important human pathogen—Aspergillus fumigatus (AFLB), which has high sn‐1,3‐specificity toward triolein. AFLB crystal structure displays a CALB‐like catalytic domain and hosts a unique tightly closed 'lid' domain that contains a disulfide bridge, as well as an extra N‐terminal subdomain composed of residues 1–128 (including the helix α1–α5 located above the active site). To gain insight into the function of this novel lid and N‐terminal subdomain, we constructed and characterized a series of mutants in these two domains. Deleting the protruding bulk lid's residues, replacing the bulk and tight lid with a small and loose lid from CALB, or breaking the disulfide bridge increased the affinity of CALB for glyceride substrates and improved its catalytic activity, along with the loss of enzyme fold stability and thermostability. N‐terminal truncation mutants revealed that the N‐terminal peptide (residues 1–59) is a strong inhibitor of AFLB binding to lipid films. This peptide thus limits AFLB's penetration power and specific activity, revealing a unique enzyme activity regulatory mechanism. Our findings on the functional and structural properties of AFLB provide a better understanding of the functions of the CALB‐like lipases and pave the way for its future protein engineering. Database: Structural data are available in the Protein Data Bank under the accession numbers 6IDY. [ABSTRACT FROM AUTHOR]

Multi‐step biocatalytic reactions have gained increasing importance in recent years because the combination of different enzymes enables the synthesis of a broad variety of industrially relevant products. However, the more enzymes combined, the more crucial it is to avoid cross‐reactivity in these cascade reactions and thus achieve high product yields and high purities. The selective control of enzyme activity, i.e. remote on‐/off‐switching of enzymes, might be a suitable tool to avoid the formation of unwanted by‐products in multi‐enzyme reactions. This review compiles a range of methods that are known to modulate enzyme activity in a stimulus‐responsive manner. It focuses predominantly on in vitro systems and is subdivided into reversible and irreversible enzyme activity control. Furthermore, a discussion section provides indications as to which factors should be considered when designing and choosing activity control systems for biocatalysis. Finally, an outlook is given regarding the future prospects of the field. [ABSTRACT FROM AUTHOR]

Abstract As alkaline phosphatase (ALP) plays crucial roles in disease warning and dephosphorylation-related cellular regulation, it is widely recognized as an important biomarker for clinical diagnosis. In this work, we proposed a facile colorimetric assay based on phosphate anion-quenched oxidase-mimicking activity of Ce(Ⅳ) ions for sensitive and selective detection of ALP activity. Free Ce(Ⅳ) ions exhibited a strong oxidase-like capability (providing a 40-fold catalytic turnover number compared with CeO 2) to catalyze the oxidation of colorless 3,3′,5,5′-tetramethylbenzidine (TMB) into its blue product TMBox mediated by dissolved O 2 at neutral pH, thus triggering a remarkable color reaction visually. When PO 4 3− was added, its strong affinity to Ce(Ⅳ) ions rapidly precipitated the free Ce(Ⅳ) ions, resulting in the quenching of their enzymatic ability. Given that ALP catalyzed the hydrolysis of adenosine triphosphate to produce PO 4 3−, determination of ALP activity could be achieved using the colorimetric assay with no need of complicated instrumentation and protocol. As demonstrated, our assay offered a highly sensitive readout for ALP activity in two linear scopes of 0–50 U L−1 and 50–250 U L−1, providing a detection limit down to 2.3 U L−1. Besides, it could provide specific response toward ALP against other enzymes and biological species. Furthermore, the developed assay was successfully applied to evaluate ALP activity in human plasma accurately and reliably, indicating its great promise as a powerful and convenient tool for monitoring of ALP activity in clinical practice. Graphical abstract Image 1 Highlights • Free Ce(Ⅳ) ions act as a potential oxidase mimic. • The homogeneous nature makes Ce(Ⅳ) ions have high oxidase-like activity. • PO 4 3− can quench the catalytic activity of Ce(Ⅳ) ions by forming precipitates. • A colorimetric assay of ALP activity is developed based on the above principle. [ABSTRACT FROM AUTHOR]

NADPH oxidases (NOXs), mostly known as respiratory burst oxidase homologs (RBOHs), are the key producers of reactive oxygen species (ROS) in plants. A lot of literature has addressed ROS signaling in plant development regulation and stress responses as well as on the enzyme’s structure, evolution, function, regulation and associated mechanisms, manifesting the role of NOXs/RBOHs as the vital performers and center hubs during plant growth and signaling. This review focuses on recent advances of NOXs/RBOHs on cell growth, hormone interaction, calcium signaling, abiotic stress responses, and immunity. Several primary particles, including Ca2+, CDPKs, BIK1, ROPs/RACs, CERK, FER, ANX, SnRK and SIK1-mediated regulatory mechanisms, are fully summarized to illustrate the signaling behavior of NOXs/RBOHs and their sophisticated and dexterous crosstalks. Diverse expression and activation regulation models endow NOXs/RBOHs powerful and versatile functions in plants to maintain innate immune homeostasis and development integrity. NOXs/RBOHs and their related regulatory items are the ideal targets for crop improvement in both yield and quality during agricultural practices.

In this work, we proposed a new and facile strategy for the high-performance colorimetric detection of Ag + based on the tunable peroxidase-like activity of Pd nanoparticles (NPs) mediated by histidine (His). Bare Pd NPs possess intrinsic catalytic ability to trigger the oxidation of colorless 3,3′,5,5′-tetramethylbenzidine (TMB) to blue TMBox in the presence of H 2 O 2 . After being decorated by His, the formed His-Pd nanozyme exhibits significantly improved mimetic activity due to its favorable physicochemical characteristics including smaller size, interactions between Pd and His, and better hydrophilicity, and such that an enhanced TMB color reaction is observed. When Ag + exists, it is able to despoil the His modifier from the His-Pd surface via the specific interaction between Ag + and His, resulting in the bald Pd again with weak activity. With this principle, highly sensitive determination of Ag + in a linear scope of 30–300 nM was achieved with a limit of detection down to 4.7 nM. In addition, the colorimetric sensor based on the tunable enzymatic activity of nanosized Pd adjusted by His could provide excellent selectivity for Ag + sensing against common interferents. Reliability of the strategy for practical detection of Ag + was also demonstrated. [ABSTRACT FROM AUTHOR]

Abstract It has been postulated that gaining control over activity in the dorsolateral prefrontal cortex (DLPFC), a key region of the working memory brain network, may be beneficial for cognitive performance and treatment of certain psychiatric disorders. Several studies have reported that, with neurofeedback training, subjects can learn to increase DLPFC activity. However, improvement of dynamic control in terms of switching between low and high activity in DLPFC brain states may potentially constitute more effective self-regulation. Here, we report on feasibility of obtaining dynamic control over DLPFC, meaning the ability to both in- and decrease activity at will, within a single functional MRI scan session. Two groups of healthy volunteers (N = 24) were asked to increase and decrease activity in the left DLPFC as often as possible during fMRI scans (at 7 Tesla), while receiving real-time visual feedback. The experimental group practiced with real-time feedback, whereas the control group received sham feedback. The experimental group significantly increased the speed of intentionally alternating DLPFC activity, while performance of the control group did not change. Analysis of the characteristics of the BOLD signal during successful trials revealed that training with neurofeedback predominantly reduced the time for the DLPFC to return to baseline after activation. These results provide a preliminary indication that people may be able to learn to dynamically down-regulate the level of physiological activity in the DLPFC, and may have implications for psychiatric disorders where DLPFC plays a role. [ABSTRACT FROM AUTHOR]

Ubiquitination, the covalent attachment of ubiquitin to proteins, by E3 ligases of the HECT (homologous to E6AP C terminus) family is critical in controlling diverse physiological pathways. Stringent control of HECT E3 ligase activity and substrate specificity is essential for cellular health, whereas deregulation of HECT E3s plays a prominent role in disease. The cell employs a wide variety of regulatory mechanisms to control HECT E3 activity and substrate specificity. Here, we summarize the current understanding of these regulatory mechanisms that control HECT E3 function. Substrate specificity is generally determined by interactions of adaptor proteins with domains in the N-terminal extensions of HECT E3 ligases. These N-terminal domains have also been found to interact with the HECT domain, resulting in the formation of inhibitory conformations. In addition, catalytic activity of the HECT domain is commonly regulated at the level of E2 recruitment and through HECT E3 oligomerization. The previously mentioned regulatory mechanisms can be controlled through protein-protein interactions, post-translational modifications, the binding of calcium ions, and more. Functional activity is determined not only by substrate recruitment and catalytic activity, but also by the type of ubiquitin polymers catalyzed to the substrate. While this is often determined by the specific HECT member, recent studies demonstrate that HECT E3s can be modulated to alter the type of ubiquitin polymers they catalyze. Insight into these diverse regulatory mechanisms that control HECT E3 activity may open up new avenues for therapeutic strategies aimed at inhibition or enhancement of HECT E3 function in disease-related pathways. [ABSTRACT FROM AUTHOR]

This work presents computer modeling of the activity of glutamine synthetase, which is a key component of nitrogen metabolism that catalyzes the synthesis of glutamine from glutamate and ammonia in an ATP-depending reaction. An algorithm based on the stochastic approach was applied to simulate the processes of substrate binding and activation. An evaluation of the effects of free Mg2+ ions on the activity of glutamine synthetase was performed and the optimal activation mechanism was determined. The major conclusion is that activation of bacterial glutamine synthetase in vivo is due to a consecutive mechanism with sequential Mg2+ ions binding first to the substrate-free form. [ABSTRACT FROM AUTHOR]

The published data on the regulation of telomerase activity are systemized. The structure and functions of telomeres and telomerase are described. The main pathways of epigenetic regulation of telomerase activity—modification of the TERT (telomerase reserve transcriptase) gene histone and its methylation— are described. Particular attention is paid to the regulation of telomerase activity at the transcriptional level (transcriptional activators and inhibitors of TERT, as well as two-way transcription regulators) and posttranscriptional regulation (alternative splicing of TERT mRNA, phosphorylation, and ubiquitination of TERT). [ABSTRACT FROM AUTHOR]

FOX family is a highly conserved transcription factor in structure, its function and molecular mechanism has gradually become a hot topic in the field of immunology, genetics, medicine and oncology. FOX transcription factor family has 19 subfamilies. FOXOs are important members of the FOX family, which contain FOXO1, FOXO3a, FOXO4 and FOXO6. These transcription factors respectively express in different tissues and organs. FOXOs are closely related with cell development and metabolism, participating in many cellular physiological processes such as oxidative stress, DNA repair, cell cycle regulation, cell apoptosis and autophagy. FOXOs also play a key role in the development of cancer, osteoporosis, cardiovascular disease, nerve tissue degradation and many other age-related diseases. The study of their function and molecular regulation mechanism can provide new ideas for the prevention and treatment of age-related diseases. In this review, we will discuss the recent advances in the researches of transcription factors FOXOs and their activity regulation, cell oxidative stress, cell cycle and apoptosis. [ABSTRACT FROM AUTHOR]

• Bifunctional catalyst was fabricated by compositing N-doped carbon with FeCo species. • Biomass potato was utilized as sustainable material. • OER performance was positively regulated by Co(OH) 2. • The catalyst exhibits satisfactory activity to ORR and OER. An N-doped carbon-based bifunctional catalyst (Po-FeCo-N-C) is prepared. Biomass potato is utilized a sustainable material and the OER performance of the catalyst is positively regulated. Potato is carbonized to N-doped carbon nanoparticles with the facilitation of carbon black to anchor more nitrogen, generating pyridinic N and graphitic N dominated ORR active sites. The Po-FeCo-N-C with 3:1 of Fe/Co ratio exhibits 0.830 V of ORR half wave potential and 5.19 mA cm−2 of current density in 0.1 M KOH. Meanwhile, 85 mV of improvement on OER potential is achieved with regulation of Co(OH) 2 , demonstrating the remarkably bifunctional catalytic activity. The rechargeable zinc-air battery of Po-FeCo-N-C outputs higher open circuit voltage, and delivers higher specific capacities, larger power densities and excellent cyclic durability. This work provides a feasible method for the preparation of nonprecious metal-based bifunctional catalyst to ORR and OER from sustainable biomass material with low cost and wide resources. [ABSTRACT FROM AUTHOR]

Antimicrobial agents have eradicated many infectious diseases and significantly improved our living environment. However, abuse of antimicrobial agents has accelerated the emergence of multidrug-resistant microorganisms, and there is an urgent need for novel antibiotics. Antimicrobial peptides (AMPs) have attracted attention as a novel class of antimicrobial agents because AMPs efficiently kill a wide range of species, including bacteria, fungi, and viruses, via a novel mechanism of action. In addition, they are effective against pathogens that are resistant to almost all conventional antibiotics. AMPs have promising properties; they directly disrupt the functions of cellular membranes and nucleic acids, and the rate of appearance of AMP-resistant strains is very low. However, as pharmaceuticals, AMPs exhibit unfavorable properties, such as instability, hemolytic activity, high cost of production, salt sensitivity, and a broad spectrum of activity. Therefore, it is vital to improve these properties to develop novel AMP treatments. Here, we have reviewed the basic biochemical properties of AMPs and the recent strategies used to modulate these properties of AMPs to enhance their safety.

The concept of human functional states (HFS) is considered in the framework of activity regulation approach developed in Russian applied psychology. Aimed at the analysis of changes in regulatory mechanisms of on-going activity, structural methods for multilevel assessment of workers’ states are discussed. Three different strategies of data integration are proposed regarding the types of essential practical problems. Their usability is exemplified with the help of two empirical studies concerned with reliability of fire-fighters’ work in the Chernobyl Zone and effects of interruptions in computerized office environment. A general framework for applied HFS research is proposed in order to develop new ecologically valid psychodiagnostic procedures that can help to create efficient stress-management programs for enhancing human reliability and performance in complex job environment.

Antibiotic-resistant bacteria and antibiotic-resistant genes have becoming one of major environmental pollutants, which lead to the increased potential risk to human health and ecological safety. Additionally, bacterial surface biofouling has caused severe problems in a range of industries, which results in considerable economic losses and even the ecological unbalance of a local environment. Therefore, alternative antimicrobial and antifouling strategies different to traditions methods are urgently needed. Nanozymes (nanomaterials with enzyme-mimicking activities)-based antibacterial and antifouling agents has drawn considerable interests owing to their intrinsic high stability and excellent environmental adaptability. In view of the great advancement of nanozymes in environmentally antibacterial and antifouling applications, we briefly summarize the classification of nanozymes relevant to environmental applications and discuss their catalytic mechanism. We also cover the regulation strategies of nanozymes activity, including tuning the intrinsic physicochemical properties of nanomaterials and changing environmental factors. Moreover, we highlight the environmental applications of nanozymes as antimicrobial and antifouling agents, especially for water treatment. Finally, the future opportunities and challenges for the advancement of nanozymes are outlined and discussed. This review not only gives the overview of the recent research of nanozymes as antimicrobial and antifouling agents for environmental applications, but also provides an important guidance for designing nanozymes. [Display omitted] • The classification of nanozyme for environmental applications and their corresponding catalytic mechanisms are introduced. • The regulation strategies of activity and selectivity of nanozyme are summarized. • The recent progress of nanozymes for environmental applications as antibacterial and antifouling materials are reviewed. • The current challenges and future focus of nanozymes for practical applications are proposed. [ABSTRACT FROM AUTHOR]